/* ===== CSS Variables ===== */
:root {
    --primary-color: #000000;
    --secondary-color: #ffffff;
    --accent-color: #4a90e2;
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --border-color: #e0e0e0;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Reset & Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

/* ===== Container ===== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    position: relative;
    color: var(--text-primary);
    font-weight: 500;
    padding: 0.5rem 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 25px;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

/* ===== Hero Section ===== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding-top: 80px;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 0;
}

.floating-shapes {
    position: absolute;
    width: 100%;
    height: 100%;
}

.shape {
    position: absolute;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(74, 144, 226, 0.1), rgba(74, 144, 226, 0.05));
    animation: float 20s infinite ease-in-out;
}

.shape-1 {
    width: 300px;
    height: 300px;
    top: 10%;
    left: 10%;
    animation-delay: 0s;
}

.shape-2 {
    width: 200px;
    height: 200px;
    top: 60%;
    right: 15%;
    animation-delay: 2s;
}

.shape-3 {
    width: 150px;
    height: 150px;
    bottom: 20%;
    left: 20%;
    animation-delay: 4s;
}

.shape-4 {
    width: 250px;
    height: 250px;
    top: 30%;
    right: 25%;
    animation-delay: 6s;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0) rotate(0deg);
    }
    25% {
        transform: translate(20px, -20px) rotate(90deg);
    }
    50% {
        transform: translate(-20px, 20px) rotate(180deg);
    }
    75% {
        transform: translate(20px, 20px) rotate(270deg);
    }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    animation: fadeInUp 1s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 5rem);
    margin-bottom: 1rem;
}

.gradient-text {
    background: linear-gradient(135deg, #1a1a1a 0%, #4a90e2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 3s ease infinite;
}

@keyframes gradientShift {
    0%, 100% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
}

.typewriter-container {
    min-height: 60px;
    margin-bottom: 1rem;
}

.typewriter-text {
    font-size: clamp(1.2rem, 3vw, 1.8rem);
    color: var(--text-secondary);
    font-weight: 500;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.2rem);
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* ===== Buttons ===== */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    transition: var(--transition);
    cursor: pointer;
    border: 2px solid transparent;
}

.btn-primary {
    background: var(--primary-color);
    color: var(--secondary-color);
    border-color: var(--primary-color);
}

.btn-primary:hover {
    background: transparent;
    color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-large {
    padding: 1.125rem 2.5rem;
    font-size: 1.1rem;
}

/* ===== Scroll Indicator ===== */
.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-indicator span {
    display: block;
    width: 24px;
    height: 40px;
    border: 2px solid var(--text-secondary);
    border-radius: 20px;
    position: relative;
}

.scroll-indicator span::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 8px;
    background: var(--text-secondary);
    border-radius: 2px;
    animation: scrollDown 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    40% {
        transform: translateX(-50%) translateY(-10px);
    }
    60% {
        transform: translateX(-50%) translateY(-5px);
    }
}

@keyframes scrollDown {
    0% {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(16px);
    }
}

/* ===== Section Styles ===== */
section {
    padding: 6rem 0;
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    text-align: center;
    margin-bottom: 1rem;
    position: relative;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 3rem;
}

/* ===== About Section ===== */
.about {
    background: var(--bg-secondary);
}

.about-content {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 4rem;
    align-items: start;
    max-width: 1000px;
    margin: 0 auto;
}

.about-image {
    position: relative;
}

.profile-photo {
    width: 100%;
    height: auto;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
    object-fit: cover;
    max-height: 400px;
}

.profile-photo:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
}

.about-intro {
    font-size: 1.3rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.8;
}

.about-details {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.detail-item h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.detail-item p {
    color: var(--text-secondary);
}

.detail-year {
    font-size: 0.9rem;
    color: var(--accent-color);
    font-weight: 600;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-link {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    transition: var(--transition);
}

.social-link svg {
    width: 24px;
    height: 24px;
}

.social-link:hover {
    border-color: var(--accent-color);
    background: var(--accent-color);
    color: white;
    transform: translateY(-3px);
}


/* ===== Services Section ===== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.service-card {
    background: var(--bg-primary);
    padding: 2.5rem 2rem;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
    cursor: pointer;
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-color);
}

.service-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-secondary);
    border-radius: 12px;
    margin-bottom: 1.5rem;
    transition: var(--transition);
}

.service-card:hover .service-icon {
    background: var(--accent-color);
    color: white;
    transform: scale(1.1);
}

.service-icon svg {
    width: 32px;
    height: 32px;
}

.service-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

.service-card p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Experience Section ===== */
.experience {
    background: var(--bg-secondary);
}

.timeline {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    padding-left: 3rem;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border-color);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
}

.timeline-dot {
    position: absolute;
    left: -3.5rem;
    top: 0;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--accent-color);
    border: 4px solid var(--bg-secondary);
    box-shadow: 0 0 0 4px var(--accent-color);
}

.timeline-content {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.timeline-content:hover {
    transform: translateX(8px);
    box-shadow: var(--shadow-md);
}

.timeline-date {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: var(--accent-color);
    color: white;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.timeline-content h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.company {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.company-link {
    color: var(--accent-color);
    font-size: 0.95rem;
    display: inline-block;
    margin-bottom: 1rem;
}

.company-link:hover {
    text-decoration: underline;
}

.timeline-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Projects Section ===== */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--bg-primary);
    border-radius: 16px;
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: var(--transition);
    cursor: pointer;
    position: relative;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color), #4a90e2);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.project-card:hover::before {
    transform: scaleX(1);
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.project-content {
    padding: 2rem;
}

.project-content h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
}

.project-content p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.tag {
    padding: 0.375rem 0.875rem;
    background: var(--bg-secondary);
    border-radius: 20px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.project-link {
    color: var(--accent-color);
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
}

.project-link:hover {
    gap: 0.75rem;
}

/* ===== Open Source Section ===== */
.opensource {
    background: var(--bg-secondary);
}

.opensource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.opensource-item {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    text-align: center;
    transition: var(--transition);
}

.opensource-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-color);
}

.opensource-item h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.opensource-item p {
    color: var(--text-secondary);
}

/* ===== Contact Section ===== */
.contact {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.contact-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.contact-description {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
    line-height: 1.8;
}

.contact-info {
    margin-bottom: 2rem;
}

.email-link {
    display: inline-flex;
    align-items: center;
    gap: 1rem;
    font-size: 1.5rem;
    color: var(--primary-color);
    padding: 1rem 2rem;
    border-radius: 12px;
    transition: var(--transition);
}

.email-link svg {
    width: 32px;
    height: 32px;
}

.email-link:hover {
    background: var(--bg-secondary);
    transform: scale(1.05);
}

.contact-social-links {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

/* ===== Footer ===== */
.footer {
    background: var(--primary-color);
    color: var(--secondary-color);
    padding: 2rem 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

.footer-links a {
    color: var(--secondary-color);
    opacity: 0.8;
    transition: var(--transition);
}

.footer-links a:hover {
    opacity: 1;
    transform: translateY(-2px);
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }

    .nav-container {
        padding: 1rem;
    }

    .nav-menu {
        position: fixed;
        left: 0;
        top: 70px;
        flex-direction: column;
        background: rgba(255, 255, 255, 0.98);
        width: 100%;
        text-align: center;
        transition: transform 0.3s ease;
        box-shadow: var(--shadow-md);
        padding: 2rem 0;
        transform: translateX(-100%);
    }

    .nav-menu.active {
        transform: translateX(0);
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .about-image {
        text-align: center;
    }

    .profile-photo {
        max-width: 250px;
        max-height: 350px;
    }

    .about-details {
        grid-template-columns: 1fr;
    }

    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 300px;
    }

    .timeline {
        padding-left: 2rem;
    }

    .timeline-dot {
        left: -2.5rem;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    section {
        padding: 4rem 0;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }

    .nav-container {
        padding: 1rem;
    }

    .shape {
        opacity: 0.5;
    }
}

/* ===== Scroll Animations ===== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== Selection ===== */
::selection {
    background: var(--accent-color);
    color: white;
}

::-moz-selection {
    background: var(--accent-color);
    color: white;
}